An analysis of the inquiry level of science activities within junior high science textbooks and their accompanying supplemental activity guides was undertaken utilizing the inquiry analysis scheme developed by Tafoya et al. (1980). The inquiry level of activities was analyzed in relation to textbook series, supplemental activity guide, and discipline. Significance was determined using two-way ANOVAs for inquiry level by publisher series activity guides, inquiry level by discipline activity guides, inquiry level by publisher textbook series, and inquiry level by discipline textbooks. Tukey's pairwise comparison was used to determine significance among two-way ANOVA means. There was a significant difference in the frequency of inquiry level of activities among science textbooks, supplemental activity guides, and disciplines.